This invention relates to a contact switching device.
It is well known that vacuum switches are advantageous in that the interrupting performance is excellent, contacts have a long lifetime and disadvantageous in that as the number of current switchings increases, the dielectric strength across the gap is not only decreased but also becomes unstable. It is also widely known that in on-load tap changers, adjacent taps may have generated thereacross impulse voltages reaching several tens the normal voltage thereacross due to lightning strokes invading the mating transformer windings. Therefore when vacuum switches are used as elements for switching currents through on-load tap changers, it is important that the disadvantages of the vacuum switch be compensated for and that the best use be made of the advantages thereof. Thus there are provided in various circuit systems and are used as a diverter switch for performing complicated and special operations.
Accordingly it is an object of the present invention to provide a new and improved contact switching device which can easily operate as a diverter switch to perform the complicated and special operation.